RV receptacle for charging.

I have a 50amp 240v RV receptacle on my property. I have read that they are not rated or safe for the constant full draw of charging an EV. Can/should I down size the breaker to 40amps for safety or am I over thinking this? It's 6/3 stranded copper wire feeding it and it's 108' from the breaker panel. I will be renting the property out on airbnb and I won't be around when guests are using it.